Generally vaginal tampons are manufactured from absorbent fibers, such as rayon, cotton, or a mixture of both fibers. In the case of digital tampons (i.e., tampons without any applicator aid) the volume of absorbent fibers necessary, to provide sufficient absorption capacity must be highly compressed to form a substantially circular tampon of sufficiently small size to allow comfortable insertion into the body. The compression must be adequate to provide the tampon with axial stability such that the circular shape is maintained until the insertion is completed. Such compression for digital vaginal tampons is typically provided as radial compression. As a result the tampon when first inserted into the body is often compressed into a relatively non-conformable form with a relatively high initial density.
A drawback associated with such digital tampons (which are currently commercially available) is that they are not able to appropriately conform to the vaginal walls after insertion. Thus menstrual fluid may flow along the tampon's side and bypass its absorbent portions. Thus such tampons are susceptible to bypass leakage.
There have been attempts to address the problem of early bypass leakage. For example WO 97/23185 discloses the use of appropriate fibre mixtures providing rapid expansion properties to a compressed tampon, like mixtures of non-limbed fibres together with multi-limbed regenerated cellulose fibers.
However, consumer needs have not been fully satisfied. There is still a need of providing digital tampons that would reduce or even prevent bypass leakage (early on and during use) while delivering effective absorption capacity.
It is a further object of the present invention to provide a digital vaginal tampon having substantial dimensional stability prior use and thus being easy to insert by digital application while exhibiting improved expansion characteristics in a wet environment (typically in use conditions).
The present invention achieves these objects by means of the features contained in the claims. It has now surprisingly been found that a digital vaginal tampon made of a cylindrical mass of compressed fibers and having the ability of radially expanding in a non-circular shape, preferably an ellipsoidal shape, upon exposure to a wet environment, provides a better adaptation to the non-circular morphology of the vagina thereby reducing bypass leakage while exhibiting effective absorption capacity.
Advantageously the tampons herein when flared by the user before digital insertion in the vagina have the tendency to take an ellipsoidal shape at the withdrawal flared end, thereby facilitating finger grip for digital insertion.